EXTRAVASATION

An escape of ﬂuid from the vessels or passages which ought to contain it. Extravasation of blood due to tearing of vessel walls is found in STROKE, and in the commoner condition known as a bruise. Extravasation of urine takes place when the bladder or the URETHRA is ruptured by a blow on the abdomen or on the crutch (PERINEUM), or torn in a fracture of the pelvis. Intravenous infusions frequently extravasate.